ByPeter N. Spotts, Staff writerSeptember 22, 2009

Tuesday's one-day UN summit on global warming provided a bully pulpit for key political leaders to lay out their hopes and requirements for a new global warming pact to replace or augment the 1997 Kyoto Protocol.

Leaders from the headliners – the US and China – sent clear, strong verbals signals that they see global warming as a serious problem and are setting out ambitious programs to deal with it in the run-up to global climate talks scheduled for Copenhagen in December.

President Obama cited a list of accomplishments his administration has achieved even as Congress works its way through an overarching energy and climate bill.

He also acknowledged that developed countries, whose factories, power plants, and transportation systems historically have been the largest emitters of heat-trapping greenhouse-gases, "still have a responsibility to lead."

But he pointedly added that developing countries with the highest economic growth rates – including China and India – will be responsible for the largest future increases in emissions.

"They will need to commit to strong measures at home and agree to stand behind those commitments just as the developed nations must stand behind their own," he said. "There is no other way."

China's President Hu Jintao in effect responded by saying Beijing is preparing to set ambitious domestic targets for reducing the carbon intensity of the country's economy. Carbon intensity is a measure of how much carbon dioxide the country's economy emits for every unit of gross domestic product.

President Hu didn't put a number on the new carbon-intensity effort, to be included in the China's 2011 five-year plan. But he indicated that a new reduction would be noteworthy.

Considering the country already has reduced its economy's energy intensity by 20 percent over the past five years, the shift to carbon intensity with a meaningful goal attached "would be significant and impressive," says Reid Detchon, vice president for energy and climate at the United Nations Foundation in Washington.

In his address, Obama also noted that the least-developed countries, who are the most ill-equipped to deal with the effects of global warming, will require financial help from richer nations if they are to adapt to global warming and "pursue low-carbon development."